Disease severity adversely affects delivery of dialysis in acute renal failure

Background/Aims: Methods of intermittent hemodialysis (IHD) dose
quantification in acute renal failure (ARF) are not well defined.
This observational study was designed to evaluate the impact of
disease activity on delivered single pool Kt/V-urea in ARF
patients. Methods: 100 patients with severe ARF (acute intrinsic
renal disease in 18 patients, nephrotoxic acute tubular necrosis in
38 patients, and septic ARF in 44 patients) were analyzed during
four consecutive sessions of IHD, performed for 3.5-5 h every other
day or daily. Target IHD dose was a single pool Kt/V-urea of 1.2 or
more per dialysis session for all patients. Prescribed Kt/V-urea
was calculated from desired dialyzer clearance (K), desired
treatment time (t) and anthropometric estimates for urea
distribution volume (V). The desired clearance (K) was estimated
from prescribed blood flow rate and manufacturer's charts of in
vivo data obtained in maintenance dialysis patients. Delivered
single pool Kt/V-urea was calculated using the Daugirdas equation.
Results: None of the patients had prescription failure of the
target dose. The delivered IHD doses were substantially lower than
the prescribed Kt/V values, particularly in ARF patients with
sepsis/septic shock. Stratification according to disease severity
revealed that all patients with isolated ARF, but none with 3 or
more organ failures and none who needed vasopressive support
received the target dose. Conclusion: Prescription of target IHD
dose by single pool Kt/V-urea resulted in suboptimal dialysis dose
delivery in critically ill patients. Numerous patient-related and
treatment-immanent factors acting in concert reduced the delivered
dose. Copyright (C) 2007 S. Karger AG, Basel.